Epidemiology ofCandidablood stream infections in patients with hematological malignancies or solid tumors

Quinalizarin as a potential antifungal drug for the treatment of Candida albicans fungal infection in cancer patients

This study aims to analyze the antifungal properties of quinalizarin, a plant-derived compound with proven anticancer effects. Quinalizarin exhibited antifungal activity against opportunistic pathogenic Candida species and Geotrichum capitatum. The treatment with this anthraquinone reduced hyphal growth, inhibited biofilm formation, and damaged mature Candida albicans biofilms. Real-time RT-PCR revealed that quinalizarin downregulated the expression of hyphae-related and biofilm-specific genes. The flow cytometry method used in the study showed that both apoptosis and necrosis were the physiological mechanisms of quinalizarin-induced C. albicans cell death, depending on the dose of the antifungal agent. A further study revealed an increase in the levels of intracellular reactive oxygen species and alterations in mitochondrial membrane potential after treatment with quinalizarin. Finally, quinalizarin was found to have low toxicity in a hemolytic test using human erythrocytes. In conclusion, we have identified quinalizarin as a potential antifungal compound.IMPORTANCEThis article is a study to determine the antifungal activity of quinalizarin (1,2,5,8-tetrahydroxyanthraquinone). Quinalizarin has potential antitumor properties and is effective in different types of tumor cells. The aim of the present study was to prove that quinalizarin can be used simultaneously in the treatment of cancer and in the treatment of intercurrent fungal infections. Quinalizarin was identified as a novel antifungal compound with low toxicity. These results may contribute to the development of a new drug with dual activity in the treatment of cancer-associated candidiasis.

Invasive Candidiasis in Patients with Solid Tumors: A Single-Center Retrospective Study

Background

Invasive candidiasis (ICs) is one of the common causes of death in patients with solid tumors. However, studies on the clinical characteristics of ICs with solid tumors are limited.

Methods

The purpose of this study was to retrospectively analyse the clinical characteristics, laboratory results and risk factor prediction of inpatients with ICs and solid tumors. We reviewed the clinical data and candida specimen information of hospitalized patients diagnosed with solid tumors combined with ICs at the First Hospital of China Medical University from January 2016 to December 2020. Multivariate logistic regression analysis was used to assess the prognostic factors associated with mortality in these patients.

Results

A total of 243 ICs patients with solid tumors were included in this study. The average ± SD age was 62.8 ± 11.7 (range: 27-93 years old), of which nearly 41% were ≥ 65 years old (99/243, 40.7%), and most were male (162/243, 66.6%). Most patients had malignant tumors of the digestive system. The most common candida was Candida parapsilosis (101/243, 41.5%), followed by Candida guilliermondii (83/243, 34.1%), Candida albicans (32/243, 13.1%), Candida glabrata (17/243, 6.9%), Candida tropicalis (7/243, 2.8%) and Candida krusei (3/243, 1.2%). Multivariate logistic regression analysis showed that the length of stay in the ICU, urinary catheter, total parenteral nutrition, stay in the ICU, renal failure and neutrophil count were prognostic factors related to death.

Conclusion

In this study, based on the clinical data of solid tumor patients with ICs in the past 5 years, the results showed that the length of stay in the ICU, urinary catheter, total parenteral nutrition, stay in the ICU, renal failure and neutrophil count were identified as the main prognostic factors. This study can be used to help clinicians carry out early intervention for high-risk patients.

Invasive candidiasis: current clinical challenges and unmet needs in adult populations

Invasive candidiasis (IC) is a serious infection caused by several Candida species, and the most common fungal disease in hospitals in high-income countries. Despite overall improvements in health systems and ICU care in the last few decades, as well as the development of different antifungals and microbiological techniques, mortality rates in IC have not substantially improved. The aim of this review is to summarize the main issues underlying the management of adults affected by IC, focusing on specific forms of the infection: IC developed by ICU patients, IC observed in haematological patients, breakthrough candidaemia, sanctuary site candidiasis, intra-abdominal infections and other challenging infections. Several key challenges need to be tackled to improve the clinical management and outcomes of IC patients. These include the lack of global epidemiological data for IC, the limitations of the diagnostic tests and risk scoring tools currently available, the absence of standardized effectiveness outcomes and long-term data for IC, the timing for the initiation of antifungal therapy and the limited recommendations on the optimal step-down therapy from echinocandins to azoles or the total duration of therapy. The availability of new compounds may overcome some of the challenges identified and increase the existing options for management of chronic Candida infections and ambulant patient treatments. However, early identification of patients that require antifungal therapy and treatment of sanctuary site infections remain a challenge and will require further innovations.

Fungemia in Hospitalized Adult Patients with Hematological Malignancies: Epidemiology and Risk Factors

Fungemia in hematologic malignancies (HM) has high mortality. This is a retrospective cohort of adult patients with HM and fungemia between 2012 and 2019 in institutions of Bogotá, Colombia. The epidemiological, clinical, and microbiological characteristics are described, and risk factors related to mortality are analyzed. One hundred five patients with a mean age of 48 years (SD 19.0) were identified, 45% with acute leukemia and 37% with lymphomas. In 42%, the HM was relapsed/refractory, 82% ECOG > 3, and 35% received antifungal prophylaxis; 57% were in neutropenia, with an average duration of 21.8 days. In 86 (82%) patients, Candida spp. was identified, and other yeasts in 18%. The most frequent of the isolates were non-albicans Candida (61%), C. tropicalis (28%), C. parapsilosis (17%), and C. krusei (12%). The overall 30-day mortality was 50%. The survival probability at day 30 in patients with leukemia vs. lymphoma/multiple myeloma (MM0 group was 59% (95% CI 46-76) and 41% (95% CI 29-58), p = 0.03, respectively. Patients with lymphoma or MM (HR 1.72; 95% CI 0.58-2.03) and ICU admission (HR 3.08; 95% CI 1.12-3.74) were associated with mortality. In conclusion, in patients with HM, non-albicans Candida species are the most frequent, and high mortality was identified; moreover, lymphoma or MM and ICU admission were predictors of mortality.

Separation and Washing of Candida Cells from White Blood Cells Using Viscoelastic Microfluidics

An early and accurate diagnosis of Candida albicans is critical for the rapid antifungal treatment of candidemia, a mortal bloodstream infection. This study demonstrates viscoelastic microfluidic techniques for continuous separation, concentration, and subsequent washing of Candida cells in the blood. The total sample preparation system contains two-step microfluidic devices: a closed-loop separation and concentration device and a co-flow cell-washing device. To determine the flow conditions of the closed-loop device, such as the flow rate factor, a mixture of 4 and 13 μm particles was used. Candida cells were successfully separated from the white blood cells (WBCs) and concentrated by 74.6-fold in the sample reservoir of the closed-loop system at 800 μL/min with a flow rate factor of 3.3. In addition, the collected Candida cells were washed with washing buffer (deionized water) in the microchannels with an aspect ratio of 2 at a total flow rate of 100 μL/min. Finally, Candida cells at extremely low concentrations (Ct > 35) became detectable after the removal of WBCs, the additional buffer solution in the closed-loop system (Ct = 30.3 ± 1.3), and further removal of blood lysate and washing (Ct = 23.3 ± 1.6).

Indwelling time of peripherally inserted central catheters and incidence of bloodstream infections in haematology patients: a cohort study

Background

We aimed to assess whether longer indwelling time of peripherally inserted central catheters (PICC) increases risk of central line associated bloodstream infections (CLABSI) in haematology patients.

Methods

Multicentre retrospective cohort study among haematology patients receiving PICCs between 2013 and 2015. Occurrence of CLABSI based on CDC definitions was assessed. We calculated incidence rates, determined risk factors for CLABSI and used Poisson regression models to assess the risk of developing CLABSI as a function of PICC dwell time. We compared diagnoses and treatment characteristics between 2013–2015 and 2015–2020.

Results

455 PICCs placed in 370 patients were included, comprising 19,063 catheter days. Median indwelling time was 26 days (range 0–385) and CLABSI incidence was 4.0 per 1000 catheter days, with a median time to CLABSI of 33 days (range 18–158). Aplastic anaemia (AA) was associated with an increased risk of CLABSI; patients undergoing autologous stem cell transplantation (SCT) were less likely to develop CLABSI. In the unadjusted analysis, PICCs with an indwelling time of 15–28 days, 29–42 days, 43–56 days and > 56 days each had an increased CLABSI incidence rate ratio of 2.4 (1.2–4.8), 2.2 (0.95–5.0), 3.4 (1.6–7.5) and 1.7 (0.9–3.5), respectively, compared to PICCs in place for < 15 days. However, after adjusting for AA and SCT, there was no significant difference in incidence rates between dwell times (p 0.067).

Conclusions

Our study shows that risk of CLABSI does not appear to increase with longer PICC indwelling time. Routine replacement of PICCs therefore is unlikely to prevent CLABSI in this population.

Analysis of Prognostic Risk Factors of Bloodstream Infections in Beijing Communities: A Retrospective Study from 2015 to 2019

Objective

This study intends to investigate the prognostic risk factors of bloodstream infection in Beijing.

Methods

This study is a clinical retrospective study. Four hundred forty-six patients with community-onset bloodstream infections (COBSI), admitted to the emergency department and inpatient department of Beijing Jishuitan Hospital from January 1, 2015, to December 31, 2019, were selected as the main research objects. According to whether the patient survives for 100 days or not, 363 cases were in the survival group, and 83 cases were in the death group. By analyzing the clinical data of the two groups of patients, the epidemiology, clinical characteristics, bacterial resistance, and risk factors affecting the prognosis of the patients were analyzed.

Results

A total of 446 pathogenic bacteria were isolated in this study, including 324 Gram-negative (G-) bacteria (72.6%), 121 Gram-positive (G+) bacteria (27.1%). The results of the study showed that there were significant differences in MDR, initial antibiotic use, solid tumor, CKD, septic shock, acute liver injury, AKI, central venous catheter, urinary catheter, blood replacement therapy, invasive operation, and use of three or more antibiotics between the two groups (p<0.05). The multiple logistic regression analysis showed that solid tumors (OR=3.339, 95% CI: (1.441, 7.734), p=0.005), combined septic shock (OR=20.729, 95% CI: (10.235, 41.982), p<0.001), indwelling catheters (OR=3.556, 95% CI: (1.538, 8.222), p=0.003) and continuous venovenous hemofiltration (CVVH, OR=19.548, 95% CI: (8.724, 35.641), p=0.003) are independent risk factors affecting the prognosis of COBSI patients. Appropriate initial antibiotic therapy is a protective factor affecting the prognosis of COBSI patients.

Conclusion

Solid tumors, combined septic shock, indwelling catheters, CVVH are independent risk factors affecting the prognosis of COBSI patients.

Vibrational Properties of Benzoxaboroles and Their Interactions with Candida albicans’ LeuRS

Benzoxaboroles have emerged over the past decade mainly due to their growing medicinal importance. Regarding the wide application of IR spectroscopy in the pharmaceutical industry, the vibrational properties of over a dozen of benzoxaboroles were described, based on results of DFT calculations as well as IR and Raman spectra measurements. Investigated series of compounds included the currently available antifungal drug (Tavaborole, AN2690) as well as its derivatives. An intense and well-isolated band corresponding to the B-OH group stretching vibrations was present in all experimental IR spectra in the range of 1446–1414 cm−1 and can be considered as characteristic for benzoxaboroles. The vibrational properties of benzoxaboroles are shown to be affected by the formation of intramolecular as well as intermolecular hydrogen bonds, which should also influence the interactions of benzoxaboroles with biomolecules and impact on their biological functions. Docking studies of the benzoxaboroles’ adenosine monophosphate (AMP) spiroboronates into the Candida albicans leucyl-RS synthetase binding pocket showed that the introduction of an amine substituent has a strong influence on their binding. The determined values of inhibition constants manifest high potential of some of the investigated molecules as possible inhibitors of that enzyme.

Infection-Related Mortality in Adults and Children Undergoing Allogeneic Hematopoietic Cell Transplantation: An Australian Registry Report

Infection-related mortality (IRM) is the most common non-relapse-related cause of death reported after allogeneic hematopoietic cell transplantation (HCT). Information on the incidence and timing of specific infective organisms and the risk factors for IRM is essential to developing prevention strategies. This report provides the first account of IRM in adults and children undergoing HCT in Australia. Between 2013 and 2018, 2705 adult and 689 pediatric first HCTs were identified from the Australasian Bone Marrow Transplant Recipient Registry database, associated with 1075 (39.7%) total overall deaths in adults and 134 (19.4%) in children. Demographics and causes of death, including infectious etiology and causative organisms, were extracted from the database for adults and children for analysis. At day +100 and 1 year post-HCT, IRM was the leading cause of early post-HCT mortality in adults, accounting for 6.2% and 9.8%, respectively; in children, IRM was the leading cause of post-HCT mortality at day +100 at 2.5% and the second highest cause of post-HCT mortality at 1 year post-HCT at 4.9%, following relapse at 5.8%. In adults, older age, transplantation not in a first complete remission (non-CR1), the use of antithymocyte globulin (ATG) or alemtuzumab, donor-positive/recipient-negative cytomegalovirus (CMV) serostatus, and acute graft-versus-host disease were significant risk factors for IRM. However, in children, age >5 years, acute lymphocytic leukemia as the primary disease, and mismatched unrelated or haploidentical donor source were predictive of IRM. Of the deaths in which an infectious etiology was reported in adults (52.4%), 49.3% were attributed to bacteria, 25.3% to fungus, 21.7% to viruses, and 3.6% to post-transplantation lymphoproliferative disorder (PTLD). The most common organisms were Pseudomonas spp, Enterococcus spp, Candida spp, Aspergillus spp, and CMV. In children where an infectious etiology was reported (64%), 13% were attributed to bacteria, 26% to fungus, 45% to viruses, and 16% to PTLD. This report highlights that IRM was the leading cause of death early post-HCT in Australia. Strategies to reduce IRM, such as individualized pre-transplantation infection risk assessment, rapid diagnostics, and prevention management strategies should be explored to determine whether these outcomes can be improved. In addition, improving the completeness and accuracy of reported data, particularly for infectious pathogens, could assist in directing management strategies to reduce IRM in HCT.

Candida albicans disorder is associated with gastric carcinogenesis

Background: Bacterial infection is associated with gastric carcinogenesis. However, the relationship between nonbacterial components and gastric cancer (GC) has not been fully explored. We aimed to characterize the fungal microbiome in GC. Methods: We performed ITS rDNA gene analysis in cancer lesions and adjacent noncancerous tissues of 45 GC cases from Shenyang, China. Obtaining the OTUs and combining effective grouping, we carried out species identifications, alpha and beta diversity analyses, and FUNGuild functional annotation. Moreover, differences were compared and tested between groups to better investigate the composition and ecology of fungi associated with GC and find fungal indicators. Results: We observed significant gastric fungal imbalance in GC. Principal component analysis revealed separate clusters for the GC and control groups, and Venn diagram analysis indicated that the GC group showed a lower OTU abundance than the control. At the genus level, the abundances of 15 fungal biomarkers distinguished the GC group from the control, of which Candida (p = 0.000246) and Alternaria (p = 0.00341) were enriched in GC, while Saitozyma (p = 0.002324) and Thermomyces (p = 0.009158) were decreased. Combining the results of Welch's t test and Wilcoxon rank sum test, Candida albicans (C. albicans) was significantly elevated in GC. The species richness Krona pie chart further revealed that C. albicans occupied 22% and classified GC from the control with an area under the receiver operating curve (AUC) of 0.743. Random forest analysis also confirmed that C. albicans could serve as a biomarker with a certain degree of accuracy. Moreover, compared with that of the control, the alpha diversity index was significantly reduced in the GC group. The Jaccard distance index and the Bray abundance index of the PCoA clarified separate clusters between the GC and control groups at the species level (p = 0.00051). Adonis (PERMANOVA) analysis and ANOVA showed that there were significant differences in fungal structure among groups (p = 0.001). Finally, FUNGuild functional classification predicted that saprotrophs were the most abundant taxa in the GC group. Conclusions: This study revealed GC-associated mycobiome imbalance characterized by an altered fungal composition and ecology and demonstrated that C. albicans can be a fungal biomarker for GC. With the significant increase of C. albicans in GC, the abundance of Fusicolla acetilerea, Arcopilus aureus, Fusicolla aquaeductuum were increased, while Candida glabrata, Aspergillus montevidensis, Saitozyma podzolica and Penicillium arenicola were obviously decreased. In addition, C. albicans may mediate GC by reducing the diversity and richness of fungi in the stomach, contributing to the pathogenesis of GC.

In Vitro Antifungal Activity and Mechanism of Ag3PW12O40 Composites against Candida Species

Fungal infections pose a serious threat to human health. Polyoxometalates (POMs) are metal–oxygen clusters with potential application in the control of microbial infections. Herein, the Ag₃PW₁₂O₄₀ composites have been synthesized and verified by Fourier transform infrared (FT-IR) spectrum, transmission electron microscopy (TEM), scanning electron microscope (SEM), elemental analysis, and X-ray diffraction (XRD). The antifungal activities of Ag₃PW₁₂O₄₀ were screened in 19 Candida species strains through the determination of minimum inhibitory concentration (MIC) by the microdilution checkerboard technique. The minimum inhibitory concentration (MIC₅₀) values of Ag₃PW₁₂O₄₀ are 2~32 μg/mL to the Candida species. The MIC₈₀ value of Ag₃PW₁₂O₄₀ to resistant clinical isolates C. albicans HL963 is 8 μg/mL, which is lower than the positive control, fluconazole (FLC). The mechanism against C. albicans HL963 results show that Ag₃PW₁₂O₄₀ can decrease the ergosterol content. The expressions of ERG1, ERG7, and ERG11, which impact on the synthesis of ergosterol, are all prominently upregulated by Ag₃PW₁₂O₄₀. It indicates that Ag₃PW₁₂O₄₀ is a candidate in the development of new antifungal agents.

Fungal Infections of the Stem Cell Transplant Recipient and Hematologic Malignancy Patients

Despite advances in chemotherapy and supportive care, morbidity and mortality remain high for patients with hematologic malignancies (HMs). Those who require hematopoietic stem cell transplantation (HSCT) often require significant immunosuppression and are subject to a variety of complications. These patients carry multiple risk factors for infectious complications, including the development of invasive fungal infections, compared with the general population. Because antifungal prophylaxis has been widely adopted, there has been a shift away from invasive candidiasis toward invasive mold infections, including breakthrough infections. For patients with HM and HSCT, we outline the epidemiology, manifestations, diagnosis, and treatment of invasive fungal infections.

Fungaemia in haematological malignancies: SEIFEM-2015 survey

BACKGROUND

Fungal infections are still a relevant challenge for clinicians involved in the cure of patients with cancer. We retrospectively reviewed charts of hospitalized patients with haematological malignancies (HMs), in which a documented fungaemia was diagnosed between January 2011 and December 2015 at 28 adult and 6 paediatric Italian Hematology Departments.

METHODS

During the study period, we recorded 215 fungal bloodstream infections (BSI). Microbiological analyses documented that BSI was due to moulds in 17 patients (8%) and yeasts in 198 patients (92%), being Candida spp identified in 174 patients (81%).

RESULTS

Mortality rates were 70% and 39% for mould and yeast infections, respectively. Infection was the main cause of death in 53% of the mould and 18% of the yeast groups. At the multivariate analysis, ECOG ≥ 2 and septic shock were significantly associated with increased mortality, and removal of central venous catheter (CVC) survival was found to be protective. When considering patients with candidemia only, ECOG ≥ 2 and removal of CVC were statistically associated with overall mortality.

CONCLUSIONS

Although candidemia represents a group of BSI with a good prognosis, its risk factors largely overlap with those identified for all fungaemias, even though the candidemia-related mortality is lower when compared to other fungal BSI. Management of fungal BSI is still a complex issue, in which both patients and disease characteristics should be focused to address a personalized approach.

Cysteine-Rich Antifungal Proteins from Filamentous Fungi are Promising Bioactive Natural Compounds in Anti-Candida Therapy

The emerging number of life-threatening invasive fungal infections caused by drug-resistant Candida strains urges the need for the development and application of fundamentally new and safe antifungal strategies in the clinical treatment. Recent studies demonstrated that the extracellular cysteine-rich and cationic antifungal proteins (crAFPs) originating from filamentous fungi, and de novo designed synthetic peptide derivatives of these crAFPs provide a feasible basis for this approach. This mini-review focuses on the global challenges of the anti-Canidia therapy and on the crAFPs as potential drug candidates to overcome existing problems. The advantages and limitations in the use of crAFPs and peptide derivatives compared to those of conventional antifungal drugs will also be critically discussed.

A powerful in vivo alternative model in scientific research: Galleria mellonella

Murine models are suggested as the gold standard for scientific research, but they have many limitations of ethical and logistical concern. Then, the alternative host models have been developed to use in many aspects especially in invertebrate animals. These models are selected for many areas of research including genetics, physiology, biochemistry, evolution, disease, neurobiology, and behavior. During the past decade, Galleria mellonella has been used for several medical and scientific researches focusing on human pathogens. This model commonly used their larvae stage due to their easy to use, non-essential special tools or special technique, inexpensive, short life span, and no specific ethical requirement. Moreover, their innate immune response close similarly to mammals, which correlate with murine immunity. In this review, not only the current knowledge of characteristics and immune response of G. mellonella, and the practical use of these larvae in medical mycology research have been presented, but also the better understanding of their limitations has been provided.

Viscoelastic Separation and Concentration of Fungi from Blood for Highly Sensitive Molecular Diagnostics

Isolation and concentration of fungi in the blood improves sensitivity of the polymerase chain reaction (PCR) method to detect fungi in blood. This study demonstrates a sheathless, continuous separation and concentration method of candida cells using a viscoelastic fluid that enables rapid detection of rare candida cells by PCR analysis. To validate device performance using a viscoelastic fluid, flow characteristics of 2 μm particles were estimated at different flow rates. Additionally, a mixture of 2 μm and 13 μm particles was successfully separated based on size difference at 100 μl/min. Candida cells were successfully separated from the white blood cells (WBCs) with a separation efficiency of 99.1% and concentrated approximately 9.9-fold at the center outlet compared to the initial concentration (~2.5 × 10⁷ cells/ml). Sequential 1st and 2nd concentration processes were used to increase the final number of candida cells to ~2.3 × 10⁹ cells/ml, which was concentrated ~92-fold. Finally, despite the undetectable initial concentration of 10¹ CFU/ml, removal of WBCs and the additional buffer solution enabled the quantitative reverse transcription (RT)-PCR detection of candida cells after the 1st concentration (Ct = 31.43) and the 2nd concentration process (Ct = 29.30).

Phenotypic and genotypic characterization of Candida species isolated from candideamia in Iran

Background and Purpose:

Candidemia is one of the most important fungal infections caused by Candida species. Infections and mortality caused by Candida species have been on a growing trend during the past two decades. The resistance of yeasts to antifungal drugs and their epidemiological issues have highlighted the importance of accurately distinguishing the yeasts at the species level. The technique applied for yeast identification should be fast enough to facilitate the imminent initiation of the appropriate therapy. Candidemia has not been studied comprehensively in Iran yet. Regarding this, the current study aimed to assess the epidemiology of candidemia at Tehran hospitals and compare the results with the previous findings.

Materials and Methods:

This study was conducted on 204 positive blood cultures obtained from 125 patients hospitalized in several hospitals located in Tehran, Iran, within a period of 13 months. The yeast isolation and species identification were accomplished using several phenotypic methods (i.e., production of germ tube in human serum, culture on CHROMagar Candida, and Corn meal agar containing Tween 80) and molecular methods, such as polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In addition, unknown cases were subjected to PCR sequencing. These methods were then compared in terms of accuracy, sensitivity, and speed of identification.

Results:

According to the results, C. albicans (62.4%) was the most common isolate, followed by C. parapsilosis (n=36, 17.5%), C. glabrata (n=18, 8.8%), C. tropicalis (n=13, 6.3%), Trichosporon asahii (n=3, 1.5%), C. kefyr (n=2, 1.0%), C. lusitaniae (n=2, 1.0%), C. intermedia (n=1, 0.5%), C. guilliermondii (n=1, 0.5%), and C. krusei (n=1, 0.5%), respectively.

Conclusion:

As the findings indicated, the most common species causing candidemia were C. albicans, C. parapsilosis, and C. glabrata, respectively. Children less than one year old and people with cancer were at higher risk for candidemia, compared to other groups. Moreover, phenotypic and molecular methods resulted in the identification of 65.2% and 96.6% of the isolates, respectively. Consequently, PCR-RFLP could be concluded as a more favorable technique for species identification.

In Vitro Anticandidal Activity and Mechanism of a Polyoxovanadate Functionalized by Zn-Fluconazole Complexes

The rise in the number of fungal infections is requiring the rapid development of novel antifungal agents. A new polyoxovanadate functionalized by Zn-fluconazole coordination complexes, Zn₃(FLC)₆V₁₀O₂₈·10H₂O (ZnFLC) (FLC = fluconazole) has been synthesized and evaluated for in vitro antifungal against Candida species. The identity of ZnFLC were confirmed by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. The antifungal activities of ZnFLC was screened in 19 Candida species strains using the microdilution checkerboard technique. The minimum inhibitory concentration (MIC₈₀) value of ZnFLC is 4 μg/mL on the azole-resistant clinical isolates of C. albicans HL973, which is lower than the positive control, FLC. The mechanism of ZnFLC against C. albicans HL973 showed that ZnFLC damaged the fungal cell membrane and reduced the ergosterol content. The expression of ERG1, ERG7, ERG11 ERG27, and ERG28, which have effects on the synthesis of ergosterol, were all significantly upregulated by ZnFLC.

Evaluation of candidemia in epidemiology and risk factors among cancer patients in a cancer center of China: an 8-year case-control study

BACKGROUND

Candidemia is the worldwide life-threaten disease, especially in cancer patients. This study was aimed to identify and evaluate the risk factors of candidemia in cancer patients, which will prompt the improvement on current therapeutic strategies and prognosis.

METHODS

A retrospective, case-control study was conducted from inpatients of Tianjin Medical University Cancer Institute and Hospital, during 2006 to 2013. Analyses were performed between cancer patients with candidemia as study case, and patients with bacterial bloodstream infections as control. Each case was matched up with two controls, for gender and inpatient duration. Candida species, clinical characteristics, risk factors and outcomes were reviewed in details.

RESULTS

Total number of 80 cases and 160 controls were enrolled and analyzed in this study. Candida albicans was identified as the most prevalent species and account for 55.0% candidemia, followed by Candida parapsilosis complex (21.3%), Candida tropicalis (8.8%), Candida glabrata complex (7.5%), Candida lusitaniae (3.8%), and Candida famata (3.8%). The crude mortality at 30-days of candidemia was up to 30.0%, which is significantly higher than bacterial bloodstream infections (p = 0.006). Logistical analysis demonstrated that total parenteral nutrition >5 days (p = 0.036), urinary catheter >2 days (p = 0.001), distant organ metastasis of cancer (p = 0.002) and gastrointestinal cancer (p = 0.042) were the independent risk factors for candidemia.

CONCLUSIONS

Candidemia showed significant higher mortality than bacterial bloodstream infections, C. albicans was cited as the primary pathogen. Total parenteral nutrition, urinary catheter, distant organ metastasis of cancer and gastrointestinal cancer are independent predictors for candidemia, this findings provides potential therapeutic targets for improving the outcome.

Time-Lapse Tracking of Candida tropicalis Biofilm Formation and the Antifungal Efficacy of Liposomal Amphotericin B

Candida species bloodstream infection, or candidemia, remains an important health issue with high morbidity and mortality. Bloodstream infections caused by Candida species are often associated with the ability of Candida to form biofilms on medical devices, such as central venous catheters. Non-albicans Candida species have been increasing gradually in clinical settings. Another Candida species, C. tropicalis, has a propensity to form biofilms and is also an independent risk factor for high morbidity and mortality in hospitalized patients. This study was conducted to investigate the process of biofilm formation by C. tropicalis and the antifungal activity of liposomal amphotericin B (LAB) against both forming biofilms and developed biofilms using time-lapse imaging. We found that C. tropicalis has a high capacity for hyphal growth and gas generation due to its high metabolic activity. Thus, we visually observed the formation of aggressive C. tropicalis biofilms, which are fast-growing biofilms. We found that LAB acts immediately and completely inhibits forming biofilms. Furthermore, we demonstrated that LAB was effective against developed C. tropicalis biofilms by reducing the growth of hyphae and morphological changes. These results suggest that LAB may be effective for the treatment of infections caused by catheter-related C. tropicalis biofilms.

The risk and clinical outcome of candidemia depending on underlying malignancy

Purpose

To assess the risk factors and outcomes associated with fungemia caused by the six most commonly occurring Candida species in patients with and without malignancies.

Methods

Analysis of the episodes of fungemia due to common Candida species in adults, based on an active hospital-based surveillance program (Paris area, France, 2002 to 2014).

Results

Of the 3417 patients (3666 isolates), 1164 (34.1%) had a solid tumor (45.7% digestive tract) and 586 (17.1%) a hematological malignancy (41.8% lymphoma, 33.5% acute leukemia). The hematology patients were significantly younger, more often pre-exposed to antifungals, more often infected by C. tropicalis, C. krusei, or C. kefyr, and more often treated in the first instance with an echinocandin. Compared with inpatients who were not in ICU at the time of fungemia, those in ICU were less frequently infected by C. parapsilosis (p < 0.02), had more recent surgery (p < 0.03), and died more frequently before day 8 and day 30 (p < 0.0001). An increase in crude mortality over time in ICU was observed only in oncology patients (p < 0.04). For all patients, lack of prescription of antifungals despite knowledge of positive blood culture increased the risk of death. The odds of being infected by a given Candida species compared with C. albicans were uneven regarding age, gender, type of malignancy, hospitalization in ICU, central venous catheter, HIV status, intravenous drug addiction, and previous exposure to antifungal drugs. Compared with C. albicans, C. glabrata (OR = 0.69 [0.54–0.89]) and C. parapsilosis (OR = 0.49 [0.35–0.67]) were associated with a decreased risk of death by day 8 and day 30.

Conclusion

The clinical context of underlying malignancy and hospitalization in ICU may be relevant to the initial management of candidemia.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-017-4743-y) contains supplementary material, which is available to authorized users.

Epidemiological and mycological characteristics of candidemia in Iran: A systematic review and meta-analysis

To date, there has been no comprehensive review of the epidemiology, risk factors, species distribution, and outcomes of candidemia in Iran. This study aimed to perform a systematic review and meta-analysis of all reported candidemia cases in Iran until December 2015. The review process occurred in three steps, namely a literature search, data extraction and statistical analyses. After a comprehensive literature search, we identified 55 cases. The mean age of patients was 46.80±24.30 years (range 1-81 years). The main risk factors for candidemia were surgery and burns (23.6%), followed by malignancies (20%), use of broad-spectrum antibiotics (18.2%), and diabetes (7.3%). Candida parapsilosis (n=17, 30.8%) was the leading agent, followed by Candida albicans (n=15, 27.3%), Candida glabrata (n=10, 18.2%), and Candida tropicalis (n=8, 14.5%). The frequencies of candidemia cases due to C. glabrata, C. parapsilosis, and C. albicans were significantly higher among patients aged>60, 21-40, and 41-60 years, respectively. Comparison of risk factors for candidemia by multiple logistic regression showed that one of the most important risk factors was surgery (OR: 4.245; 95% CI: 1.141-15.789; P=0.031). The outcome was recorded in only 19 cases and 13 of those patients (68.4%) expired. This study confirms that knowledge of the local epidemiology is important when conducting surveillance studies to prevent and control candidemia and will be of interest for antifungal stewardship.

Inhibitory activity of hinokitiol against biofilm formation in fluconazole-resistant Candida species

The aim of this study was to investigate the ability of hinokitiol to inhibit the formation of Candida biofilms. Biofilm inhibition was evaluated by quantification of the biofilm metabolic activity with XTT assay. Hinokitiol efficiently prevented biofilm formation in both fluconazole-susceptible and fluconazole-resistant strains of Candida species. We determined the expression levels of specific genes previously implicated in biofilm development of C. albicans cells by real-time RT-PCR. The expression levels of genes associated with adhesion process, HWP1 and ALS3, were downregulated by hinokitiol. Transcript levels of UME6 and HGC1, responsible for long-term hyphal maintenance, were also decreased by hinokitiol. The expression level of CYR1, which encodes the component of signaling pathway of hyphal formation-cAMP-PKA was suppressed by hinokitiol. Its upstream general regulator RAS1 was also suppressed by hinokitiol. These results indicate that hinokitiol may have therapeutic potential in the treatment and prevention of biofilm-associated Candida infections.

The Changing Epidemiology of Invasive Fungal Infections

Invasive fungal infections (IFI) are an emerging problem worldwide with invasive candidiasis and candidemia responsible for the majority of cases. This is predominantly driven by the widespread adoption of aggressive immunosuppressive therapy among certain patient populations (e.g., chemotherapy, transplants) and the increasing use of invasive devices such as central venous catheters (CVCs). The use of new immune modifying drugs has also opened up an entirely new spectrum of patients at risk of IFIs. While the epidemiology of candida infections has changed in the last decade, with a gradual shift from C. albicans to non-albicans candida (NAC) strains which may be less susceptible to azoles, these changes vary between hospitals and regions depending on the type of population risk factors and antifungal use. In certain parts of the world, the incidence of IFI is strongly linked to the prevalence of other disease conditions and the ecological niche for the organism; for instance cryptococcal and pneumocystis infections are particularly common in areas with a high prevalence of HIV disease. Poorly controlled diabetes is a major risk factor for invasive mould infections. Environmental factors and trauma also play a unique role in the epidemiology of mould infections, with well-described hospital outbreaks linked to the use of contaminated instruments and devices. Blastomycosis is associated with occupational exposure (e.g., forest rangers) and recreational activities (e.g., camping and fishing).The true burden of IFI is probably an underestimate because of the absence of reliable diagnostics and lack of universal application. For example, the sensitivity of most blood culture systems for detecting candida is typically 50 %. The advent of new technology including molecular techniques such as 18S ribosomal RNA PCR and genome sequencing is leading to an improved understanding of the epidemiology of the less common mould and dimorphic fungal infections. Molecular techniques are also providing a platform for improved diagnosis and management of IFI.Many factors affect mortality in IFI, not least the underlying medical condition, choice of therapy, and the ability to achieve early source control. For instance, mortality due to pneumocystis pneumonia in HIV-seronegative individuals is now higher than in seropositive patients. Of significant concern is the progressive increase in resistance to azoles and echinocandins among candida isolates, which appears to worsen the already significant mortality associated with invasive candidiasis. Mortality with mould infections approaches 50 % in most studies and varies depending on the site, underlying disease and the use of antifungal agents such as echinocandins and voriconazole. Nevertheless, mortality for most IFIs has generally fallen with advances in medical technology, improved care of CVCs, improved diagnostics, and more effective preemptive therapy and prophylaxis.

Candidemia in patients with prolonged fever in Kashan, Iran

Background and Purpose:

Candida species are considered a common cause of fungal blood stream infections, which are associated with considerable mortality and morbidity rates, especially in the admitted and immunocompromised patients. Despite the increase in new and available antifungal agents, the emergence of resistant strains is growing. Regarding this, the aim of the present study was to assess the fungal epide­miology of candidemia and the antifungal susceptibility patterns against five current antifungal agents among the patients with prolonged fever, who were admitted to Beheshti Educational Hospital, Kashan, Iran.

Materials and Methods:

This cross-sectional study was conducted on 253 hospitalized patients with prolonged fever despite receiving broad-spectrum antibiotic therapy. Blood samples were collected aseptically, and then cultured using an automated blood culture system and conventional broth culture bottle. Candida isolates were identified at species level using morphological and physiological properties and produced color on the CHROMagar Candida. Furthermore, the antifungal susceptibility testing was performed using (CLSI M27-A3 and CLSI M27-S4) broth microdilution methods.

Results:

The most positive cultures were detected by the automated blood culture system. C.albicans (%50) was the most prevalent species, followed by C. glabrata (%40), and C. parapsilosis, (%10) respectively .The mortality rate was high (%60) and most patients with candidemia were admitted to the Intensive Care Unit and Neonatal Intensive Care Unit. All isolates were susceptible to amphotericin B, while the highest resistance belonged to caspofungin.

Conclusion:

In this study, high resistance was reported, especially for caspofungin, which can be regarded as the emergence of caspofungin-resistant strains. Regarding this, the establishment of a surveillance and prevention program for the reduction of the emergence of resistant species is necessary.

Prevalence and factors predictive of intraocular fungal infection in patients with fungemia at an academic urban tertiary care center

Objective

To report the prevalence and to identify factors predictive of intraocular infection in patients with fungemia receiving prophylactic antifungal therapy.

Methods

A retrospective review of patients who received prophylactic antifungal therapy and a dilated fundus examination at an academic urban tertiary care center from 2000 to 2007. Basic demographic information, fungal species grown, antifungal agent(s) used, number of positive blood culture specimens, visual acuity, visual symptoms, and known risks of disseminated candidiasis were noted. Logistic regression analysis was used to determine the factors significantly associated with intraocular fungal infection.

Results

A total of 132 patients with positive fungemia culture were requested to have ophthalmology consults. The prevalence of ocular infection was 6.9% (N=9). All nine patients were infected with Candida species. Undergoing gastrointestinal (GI) surgery within the prior 6 months was significantly related to developing intraocular infection, with an odds ratio of 18.5 (95% confidence interval, 15.1–24.3; P=0.002). Having ≥3 positive fungal blood cultures was also a significant risk factor, with an odds ratio of 2.6 (95% confidence interval, 1.8–3.7; P=0.03). Among 40 patients having GI surgery, eight (20.0%) had intraocular fungal disease, compared with one of 92 patients (1.1%) not having GI surgery. Among 125 patients with a negative baseline examination result, two of 32 patients (6.3%), who had recent GI surgery, subsequently developed fungal ocular disease, compared with 0 of 93 patients (0%), who did not have recent GI surgery.

Conclusion

Recent GI surgery and higher numbers of positive fungal blood culture specimens may be predictive of candida ocular infections. Normal baseline fundoscopy examination results in patients with such risks may require repeat evaluations to detect delayed manifestations.

Novel antifungal drugs against fungal pathogens: do they provide promising results for treatment?

The febrile neutropenia episodes of hematological patients and their outcomes were evaluated with respect to fungal pathogens and antifungal therapy in this retrospective study. All patients, who were older than 14 years of age and developed at least one neutropenic episode after chemotherapy due to hematological cancer from November 2010 to November 2012, were included into the study. We retrospectively collected demographic, treatment, and survival data of 126 patients with neutropenia and their 282 febrile episodes. The mean Multinational Association for Supportive Care in Cancer score was 17.18 ± 8.27. Systemic antifungal drugs were initiated in 22 patients with 30 culture-proven invasive fungal infections (IFIs), 25 attacks of 19 patients with probable invasive pulmonary aspergillosis (IPA), 42 attacks of 38 patients with possible IPA, and 31 attacks of 30 patients with suspected IFI. Voriconazole (VOR), caspofungin and liposomal amphotericin B were used to treat 72 episodes of 65 patients, 45 episodes of 37 patients and 34 episodes of 32 patients as a first-line therapy, respectively. Unfavorable conditions of our hematology ward are thought to increase the number of cases with invasive pulmonary aspergillosis and VOR use. It should be taken into consideration that increased systemic and per oral VOR usage predisposes patients to colonization and infection with azole-resistant fungal strains. Catheters should be removed in cases where patients' conditions are convenient to remove it. Acute myeloblastic leukemia cases that are more likely to develop invasive fungal infections should be monitored closely for early diagnosis and timely initiation of antifungal drugs which directly correlates with survival rates.

Synergistic antifungal activity of berberine derivative B-7b and fluconazole

Our previous study demonstrated berberine (BBR) and fluconazole (FLC) used concomitantly exhibited a synergism against FLC-resistant Candida albicans in vitro. We also suggested BBR played a major antifungal role in the synergism of FLC and BBR, while FLC increased intracellular BBR concentrations. Our following systematic structural modification and reconstruction of BBR core identified the novel scaffold of N-(2-(benzo[d][1,3]dioxol-5-yl)ethyl)-2-(substituted phenyl)acet-amide derivatives 7a-i, including B-7b and B-7d exhibiting remarkable synergistic antifungal activity and low cytotoxicity. Here, the study mainly investigated the synergistic activity of FLC and B-7b and the underlying mechanism. In vitro interaction of FLC and B-7b was investigated against 30 FLC-resistant clinical isolates of C. albicans and non-C. albicans species, including Candida tropicalis, Candida parapsilosis, Candida glabrata, Candida krusei and Cryptococcus neoformans. The potent synergistic activity of B-7b in combination with FLC against FLC-resistant C. albicans was found through the checkerboard microdilution assay. The findings of agar diffusion tests and time-kill curves confirmed its better synergism with FLC. And as expected, B-7b exhibited much lower cytotoxicity than BBR to human umbilical vein endothelial cells. In contrast to BBR, we found that endogenous ROS augmentation was not involved in the synergism of FLC and B-7b. According to the results from our present comparative proteomic study, it seemed that the disruption of protein folding and processing and the weakening of cells' self-defensive ability contributed to the synergism of FLC and B-7b. Together, these results suggested novel scaffold BBR derivative B-7b could be a promising synergist in combination with FLC for the treatment of invasive fungal infections.

Molecular surveillance of candidemia due to Candida albicans among cancer patients during 2009 to 2013 by microsatellite typing

BACKGROUND

Since the high morbidity and mortality of candidemia among cancer patients, the epidemiology has been underlined. In recent years, Candida species genotyping has been established, which could provide detail characteristics of epidemiology and has been underscored for candidemia preventing strategies.

METHODS

Data of cancer patients with candidemia and hospitalized in Tianjin Medical University Cancer Institute and Hospital (TMUCIH) during 2009-2013 were reviewed. Species identification was carried out by using VITEK-2 Compact. Microsatellite typing was performed for molecular analysis. SPSS 20.0 and MVSP 3.22 software were used for statistical and clustering analysis, respectively.

RESULTS

Total of 36 isolates of Candida albicans were recovered from 36 cancer patients with nosocomial candidemia in TMUCIH during the period of 2009-2013 included in the study. Total of 17 genotypes were identified and 2 of them were endemic genotypes, which caused 21 (58.3%) of 36 episodes of candidemia. Hepatobiliary oncology, ICU and gastrointestinal oncology were the main wards of infections due to endemic strains. Gastrointestinal cancer and insertion of a nasogastric tube were the predictors of infections caused by endemic strains (p = 0.014 and p = 0.041, respectively). For the 36 cases, crude mortality was up to 30.6%, and there was no significant difference between infections due to endemic and non-endemic strains (p = 0.077).

CONCLUSIONS

This study proved that endemic stains of C. albicans could exist for a long period and mainly in a few wards. Patients with gastrointestinal cancer or nasogastric tube insertion were more sensitive to endemic C. albicans.

Efficacy and safety of echinocandins versus triazoles for the prophylaxis and treatment of fungal infections: a meta-analysis of RCTs

Echinocandins and triazoles were proven to be effective antifungal drugs against invasive fungal infections (IFI), which may cause significant morbidity and mortality in immunocompromised patients. The aim of this study was to compare the efficacy and safety between echinocandins and triazoles for the prophylaxis and treatment of fungal infections. PubMed, Embase, and the Cochrane Library were searched to identify relevant randomized controlled trials (RCTs) up to July 2014. The quality of trials was assessed with the Jadad scoring system. The primary outcomes of interest were treatment success, microbiological success, breakthrough infection, drug-related adverse events (AEs), withdrawals due to AEs, and all-cause mortality. Ten RCTs, involving 2,837 patients, were included, as follows: caspofungin versus fluconazole (n = 1), caspofungin versus itraconazole (n = 1), anidulafungin versus fluconazole (n = 1), micafungin versus fluconazole (n = 4), micafungin versus voriconazole (n = 2), and micafungin versus itraconazole (n = 1). Echinocandins and triazoles showed similar effects in terms of favorable treatment success rate [relative risk (RR) = 1.02, 95 % confidence interval (CI), 0.97–1.08], microbiological success rate (RR = 0.98, 95 % CI, 0.90–1.15), breakthrough infection (RR = 1.09; 95 % CI, 0.59–2.01), drug-related AEs (RR = 0.94; 95 % CI, 0.71–1.15), and all-cause mortality (RR = 0.85; 95 % CI, 0.66–1.10) in the prophylaxis and treatment of fungal infections. Additionally, echinocandins were more effective than triazoles for prophylaxis in patients undergoing hematologic malignancies or those who received hematopoietic stem cell transplantation (HSCT; RR = 1.08; 95 % CI, 1.02–1.15). Echinocandins significantly decreased the AE-related withdrawals rate compared with triazoles (RR = 0.47; 95 % CI, 0.33–0.67). This meta-analysis revealed that echinocandins are as effective and safe as triazoles for the prophylaxis and treatment of patients with fungal infections.

Risk factors and outcome in patients with primary sclerosing cholangitis with persistent biliary candidiasis

Background

Candidiasis is commonly observed in patients with primary sclerosing cholangitis (PSC), but the clinical risk factors associated with its presence have not been fully investigated. In this study, we aimed to analyse the incidence, risk factors, and transplantation-free survival in primary sclerosing cholangitis (PSC) patients with persistent biliary candidiasis.

Methods

We retrospectively analysed patients diagnosed with PSC who were admitted to our department during 2002 to 2012. One-hundred fifty patients whose bile cultures were tested for fungal species were selected, and their clinical and laboratory parameters were investigated. The results of endoscopic retrograde cholangiography (ERC) and bile cultures were analysed using chart reviews. The cases of biliary candidiasis were sub-classified as transient or persistent.

Results

Thirty out of 150 (20.0%) patients had biliary candidiasis. Although all patients demonstrated comparable baseline characteristics, those with biliary candidiasis showed significantly reduced transplantation-free survival (p < 0.0001) along with a markedly elevated frequency of cholangiocarcinoma (CCA) (p = 0.04). The patients were further sub-classified according to the transient (15/30) or persistent (15/30) nature of their biliary candidiasis. A subgroup analysis showed reduced survival with a greater necessity for orthotopic liver transplantation (OLT) only in patients with persistence of Candida (p = 0.007). The survival in the patients with transient biliary candidiasis was comparable to that in candidiasis-free patients. In a multivariate regression analysis that included Mayo risk score (MRS), sex, age, dominant stenosis, inflammatory bowel disease, autoimmune hepatitis overlap syndrome, and number of times ERC was performed, biliary candidiasis was an independent risk factor for reduced survival (p = 0.008). Risk factors associated with acquisition of biliary candidiasis were age at PSC diagnosis and number of ERCs.

Conclusions

The persistence of biliary candidiasis is associated with markedly reduced transplantation-free survival in PSC patients. By contrast, actuarial survival in patients with transient biliary candidiasis approaches that for patients without any evidence of biliary candidiasis. Further studies on the treatment of persistent biliary candidiasis in patients with PSC are warranted.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-014-0562-8) contains supplementary material, which is available to authorized users.

Characteristics of hospital-acquired and community-onset blood stream infections, South-East Austria

Purpose

The objective of this study was to compare epidemiology, causative pathogens, outcome, and levels of laboratory markers of inflammation of community-onset (i.e. community-acquired and healthcare-associated) and hospital-acquired bloodstream infection (BSI) in South-East Austria.

Methods

In this prospective cohort study, 672 patients fulfilling criteria of systemic inflammatory response syndrome with positive peripheral blood cultures (277 community-onset [192 community-acquired, 85 healthcare-associated BSI], 395 hospital-acquired) were enrolled at the Medical University of Graz, Austria from 2011 throughout 2012. Clinical, microbiological, demographic as well as outcome and laboratory data was collected.

Results

Escherichia coli followed by Staphylococcus aureus were the most frequently isolated pathogens. While Streptococcus spp. and Escherichia coli were isolated more frequently in patients with community-onset BSI, Enterococcus spp., Candida spp., Pseudomonas spp., Enterobacter spp., and coagulase-negative staphylococci were isolated more frequently among those with hospital-acquired BSI. With regard to the outcome, 30-day (82/395 vs. 31/277; p = 0.001) and 90-day mortality (106/395 vs. 35/277; p<0.001) was significantly higher among patients with hospital-acquired BSI even though these patients were significantly younger. Also, hospital-acquired BSI remained a significant predictor of mortality in multivariable analysis. At the time the blood cultures were drawn, patients with community-onset BSI had significantly higher leukocyte counts, neutrophil-leucocyte ratios as well as C-reactive protein, procalcitonin, interleukin-6 and serum creatinine levels when compared to those with hospital-acquired BSI. Patients with healthcare-associated BSI presented with significantly higher PCT and creatinine levels than those with community-acquired BSI.

Conclusions

Hospital-acquired BSI was associated with significantly higher 30- and 90-day mortality rates. Hospital-acquired BSI therefore poses an important target for the most aggressive strategies for prevention and infection control.

Synergistic antifungal effect of glabridin and fluconazole

The incidence of invasive fungal infections is increasing in recent years. The present study mainly investigated glabridin (Gla) alone and especially in combination with fluconazole (FLC) against Cryptococcus neoformans and Candida species (Candida albicans, Candida tropicalis, Candida krusei, Candida parapsilosis and Candida Glabratas) by different methods. The minimal inhibitory concentration (MIC) and the minimal fungicidal concentration (MFC) indicated that Gla possessed a broad-spectrum antifungal activity at relatively high concentrations. After combining with FLC, Gla exerted a potent synergistic effect against drug-resistant C. albicans and C. tropicalis at lower concentrations when interpreted by fractional inhibitory concentration index (FICI). Disk diffusion test and time-killing test confirming the synergistic fungicidal effect. Cell growth tests suggested that the synergistic effect of the two drugs depended more on the concentration of Gla. The cell envelop damage including a significant decrease of cell size and membrane permeability increasing were found after Gla treatment. Together, our results suggested that Gla possessed a synergistic effect with FLC and the cell envelope damage maybe contributed to the synergistic effect, which providing new information for developing novel antifungal agents.

Candida albicans and cancer: Can this yeast induce cancer development or progression?

There is currently increasing concern about the relation between microbial infections and cancer. More and more studies support the view that there is an association, above all, when the causal agents are bacteria or viruses. This review adds to this, summarizing evidence that the opportunistic fungus Candida albicans increases the risk of carcinogenesis and metastasis. Until recent years, Candida spp. had fundamentally been linked to cancerous processes as it is an opportunist pathogen that takes advantage of the immunosuppressed state of patients particularly due to chemotherapy. In contrast, the most recent findings demonstrate that C. albicans is capable of promoting cancer by several mechanisms, as described in the review: production of carcinogenic byproducts, triggering of inflammation, induction of Th17 response and molecular mimicry. We underline the need not only to control this type of infection during cancer treatment, especially given the major role of this yeast species in nosocomial infections, but also to find new therapeutic approaches to avoid the pro-tumor effect of this fungal species.

Epidemiology and prognostic factors of candidemia in cancer patients

Aim

The study of candidemia in cancer patients has been limited. This retrospective study aims to investigate the epidemiologic characteristics and prognostic factors of candidemia among cancer patients.

Materials and Methods

From 2009 to 2012, cancer patients with candidemia were identified at a hospital in Taiwan. The medical records of all patients with bloodstream infections due to Candida species were retrospectively reviewed.

Results

During the four-year period, a total of 242 episodes of candidemia were identified among cancer patients. Half of these patients were classified as elderly (≥65 years old), and more than 95% of the candidemia episodes were classified as healthcare-associated infections. Among the 242 cancer patients with candidemia, head and neck cancer was the most common, followed by gastrointestinal tract and lung cancer. Additionally, most of the patients had variable underlying conditions, such as the presence of CVC (99%) or prior exposure to broad-spectrum antibiotics (93%) and were receiving an immunosuppressant (86%). Overall, C. albicans (n = 132, 54.5%) was the most common pathogen, followed by C. tropicalis (n = 52, 21.5%), C. parapsilosis (n = 38, 15.7%), and C. glabrata (n = 29, 12.0%). Seventeen patients had polycandidal candidemia, and 77 patients had concomitant bacteremia. Approximately one-third of the patients required admission to the intensive care unit (ICU) or mechanical ventilation, and the overall in-hospital mortality was 50.8%. Multivariable analysis showed that the in-hospital mortality was significantly associated with only the non-use of antifungal agents and acute respiratory failure (P<.001).

Conclusions

Candidemia can develop in patients with both solid cancer and hematological malignancy, especially for patients with underlying conditions. Overall, the associated morbidity and mortality due to Candidemia remain high. It was also determined that the non-use of antifungal agents and acute respiratory failure conditions were associated with in-hospital mortality.

Epidemiology, species distribution and outcome of nosocomial Candida spp. bloodstream infection in Shanghai

Background

Yeasts, mostly Candida, are important causes of bloodstream infections (BSI), responsible for significant mortality and morbidity among hospitalized patients. The epidemiology and species distribution vary from different regions. The goals of this study were to report the current epidemiology of Candida BSI in a Shanghai Teaching Hospital and estimate the impact of appropriate antifungal therapy on the outcome.

Methods

From January 2008 to December 2012, all consecutive patients who developed Candida BSI at Ruijin University Hospital were enrolled. Underlying diseases, clinical severity, species distribution, antifungal therapy and its impact on the outcome were analyzed.

Results

A total of 121 episodes of Candida BSI were identified, with an incidence of 0.32 episodes/1,000 admissions (0.21 in 2008 and 0.42 in 2012) The proportion of candidemia caused by non-albicans species (62.8%), including C. parapsilosis (19.8%), C. tropicalis (14.9%), C. glabrata (7.4%), C. guilliermondii (5.8%), C. sake (5.0%) was higher than that of candidemia caused by C. albicans (37.2%). The overall crude 28-day mortality was 28.1% and significantly reduced with appropriate empiric antifungal therapy administered within 5 days (P = 0.006). Advanced age (OR 1.04; P = 0.014), neutropenia < 500/mm³ (OR 17.44; P < 0.001) were independent risk factors for 28-day mortality, while appropriate empiric antifungal therapy (OR 0.369; P = 0.035) was protective against 28-day mortality.

Conclusion

The epidemiology of candidemia in Shanghai differed from that observed in Western countries. Appropriate empiric antifungal therapy influenced the short-term survival.

Epidemiology of candidemia in Qatar, the Middle East: performance of MALDI-TOF MS for the identification of Candida species, species distribution, outcome, and susceptibility pattern

INTRODUCTION

Bloodstream infections (BSIs) due to Candida spp. constitute the predominant group of hospital-based fungal infections worldwide. A retrospective study evaluated the performance of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of BSI Candida isolates. The epidemiology, risk factors, demographic features, species distribution, and clinical outcome associated with candidemia in patients admitted to a single tertiary-care hospital in Qatar, were analyzed.

METHODS

A single-center, retrospective analysis covering the period from January 1, 2004 to December 31, 2010 was performed. Molecular identification used sequence analysis of the D1/D2 domains of the large subunit ribosomal DNA (LSU rDNA) and the ITS1/2 regions of the rDNA. MALDI-TOF MS-based identification of all yeast isolates was performed with the ethanol/formic acid extraction protocol according to Bruker Daltonics (Bremen, Germany). The susceptibility profiles of 201 isolates to amphotericin B, itraconazole, fluconazole, voriconazole, anidulafungin, caspofungin, posaconazole, and isavuconazole were tested using CLSI standard broth microdilution method (M27-A3 and M27 S4) guidelines. Statistical analyses were performed with the statistical package SPSS 19.0.

RESULTS

A total of 187 patients with 201 episodes of candidemia were identified. Candida albicans was the most common species isolated (33.8 %; n = 68), whereas non-albicans Candida species represented 66.2 % (n = 133) of the episodes. The species distribution and outcome of candidemia showed a difference in the crude mortality between patients infected with C. albicans (n = 30; 45.5 %) and non-albicans Candida species. For example, C. parapsilosis candidemia was associated with the lowest mortality rate (40.6 %), and patients with other non-albicans species had the highest mortality rate (68-71.4 %). High mortality rates were observed among pediatric (<1 year of age) and elderly patients (>60 years of age). All strains showed low minimum inhibitory concentrations (MICs) (MIC90 of 0.063 μg/ml) to isavuconazole. The overall resistance to voriconazole in vitro antifungal activity was 2.5 %. C. glabrata (n = 38) had an MIC90 of 8 μg/ml for fluconazole. Most yeast isolates were susceptible to anidulafungin (>99.5 %) and 81.1 % to caspofungin. Resistance to anidulafungin was detected in 1/8 (12.5 %) isolates of C. orthopsilosis. According to new Clinical and Laboratory Standards Institute (CLSI) breakpoints, C. glabrata (n = 38) showed 100 % resistance, and 37/68 (54.4 %) C. albicans isolates were susceptible dose dependent (SDD) to caspofungin. Identification by MALDI-TOF MS was in 100 % concordance with molecular identification.

CONCLUSION

The Middle East epidemiology of candidemia has a unique species distribution pattern distinct from other parts of the globe. High mortality rates were observed among pediatric (<1 year of age) and elderly patients (>60 years of age). All strains were susceptible to isavuconazole. All isolates of C.glabrata were resistant to caspofungin based on M27 S4. MALDI-TOF MS is a highly useful method for the routine identification of yeast isolates in clinical setting to achieve successful therapeutic treatment.

Experimental biofilm-related Candida infections

AIM

We investigated the pathogenic role of biofilm and the therapeutic efficacy of anidulafungin in experimental infections of the wax moth Galleria mellonella by Candida albicans clinical strains.

MATERIALS & METHODS

On the basis of the in vitro propensity to form biofilm, five biofilm-producer (BP) and four nonproducer (NP) C. albicans clinical strains were used in this study. For each strain, we assessed the virulence by infecting G. mellonella larvae and observing survival. Anidulafungin was administered 2 h after yeast inoculum at 0.6 µg, according to the therapeutic dose recommended for humans.

RESULTS

Biofilm-forming ability highly influenced the larva-killing rate. A significant (p < 0.0001) survival decrease was observed in the BP group, with 80% of the infected larvae dying within 72 h. NP isolates did not reach the same killing rate, even at the end of experiments (216 h). Larval survival was enhanced (p < 0.0001) by anidulafungin administration in both groups. Survival rate at 72 h was similar in both groups (BP 78.5% and NP 87.5%); whereas there were still differences at the end of the experiments, with a higher survival in the NP group (75 vs 48%).

CONCLUSION

Our data confirm the pathogenic role of biofilm in C. albicans infections. Its importance was further enhanced by a lack of contribution from extracellular enzymes, detected in both NP and BP strains. In addition, we demonstrated anidulafungin efficacy in treating biofilm-related invasive candidiasis.

A prospective, cohort, multicentre study of candidaemia in hospitalized adult patients with haematological malignancies

Invasive candidiasis is a life-threatening infection in patients with haematological malignancies. The objective of our study was to determine the incidence, microbiological characteristics and clinical outcome of candidaemia among hospitalized adult patients with haematological malignancies. This is a population-based, prospective, multicentre study of patients ≥ 18 years admitted to haematology and/or haematopoietic stem cell transplantation units of nine tertiary care Greek hospitals from January 2009 through to February 2012. Within this cohort, we conducted a nested case-control study to determine the risk factors for candidaemia. Stepwise logistic regression was used to identify independent predictors of 28-day mortality. Candidaemia was detected in 40 of 27,864 patients with haematological malignancies vs. 967 of 1,158,018 non-haematology patients for an incidence of 1.4 cases/1000 admissions vs. 0.83/1000 respectively (p <0.001). Candidaemia was caused predominantly (35/40, 87.5%) by non-Candida albicans species, particularly Candida parapsilosis (20/40, 50%). In vitro resistance to at least one antifungal agent was observed in 27% of Candida isolates. Twenty-one patients (53%) developed breakthrough candidaemia while receiving antifungal agents. Central venous catheters, hypogammaglobulinaemia and a high APACHE II score were independent risk factors for the development of candidaemia. Crude mortality at day 28 was greater in those with candidaemia than in control cases (18/40 (45%) vs. 9/80 (11%); p <0.0001). In conclusion, despite antifungal prophylaxis, candidaemia is a relatively frequent infection associated with high mortality caused by non-C. albicans spp., especially C. parapsilosis. Central venous catheters and hypogammaglobulinaemia are independent risk factors for candidaemia that provide potential targets for improving the outcome.

Diagnostic value of immunoglobulin G antibodies against Candida enolase and fructose-bisphosphate aldolase for candidemia

Background

The yeast Candida is one of the most frequent pathogens isolated from bloodstream infections and is associated with significant morbidity and mortality. Problems with clinical and microbiological diagnosis of invasive candidiasis (IC) have prompted the development of non-culture-based laboratory methods. Previous reports suggest that serological detection of antibodies might be useful for diagnosing systemic candidiasis.

Methods

Diagnosis of IC using antibodies against recombinant Candida albicans enolase (Eno) and fructose-bisphosphate aldolase (Fba1) was evaluated. Using recombinant Eno and Fba1 as coating antigens, enzyme-linked immunosorbent assays (ELISAs) were used to analyze sera from patients with candidemia (n = 101), Candida colonization (n = 50), bacteremia (n = 84), invasive aspergillosis (n = 40); and from healthy controls (n = 200).

Results

The results demonstrated that ELISA detection of anti-Eno and anti-Fba1 IgG distinguished IC from other pathogenic infections in patients and healthy individuals. The sensitivity, specificity, and positive and negative predictive values were 72.3%, 94.7%, 78.5% and 93% for anti-Eno, and 87.1%, 92.8%, 76.5% and 96.4% for anti-Fba1 antibodies, respectively. Combining these two tests improved sensitivity up to 90.1% and negative predictive value up to 97.1%, with specificity and positive predictive values of 90.6% and 72.2%. The tests were specific to the Candida genus and antibody titers were higher for candidemia patients than for controls. Positive antibody tests were obtained before blood culture results for 42.2% of patients for anti-Eno and 51.1% for anti-Fba1.

Conclusion

These data suggest that tests that detect IgG antibodies against Candida enolase and fructose-bisphosphate aldolase, especially when used in combination, could be a powerful tool for diagnosing IC.

ESCMID* guideline for the diagnosis and management of Candida diseases 2012: adults with haematological malignancies and after haematopoietic stem cell transplantation (HCT)

Fungal diseases still play a major role in morbidity and mortality in patients with haematological malignancies, including those undergoing haematopoietic stem cell transplantation. Although Aspergillus and other filamentous fungal diseases remain a major concern, Candida infections are still a major cause of mortality. This part of the ESCMID guidelines focuses on this patient population and reviews pertaining to prophylaxis, empirical/pre-emptive and targeted therapy of Candida diseases. Anti-Candida prophylaxis is only recommended for patients receiving allogeneic stem cell transplantation. The authors recognize that the recommendations would have most likely been different if the purpose would have been prevention of all fungal infections (e.g. aspergillosis). In targeted treatment of candidaemia, recommendations for treatment are available for all echinocandins, that is anidulafungin (AI), caspofungin (AI) and micafungin (AI), although a warning for resistance is expressed. Liposomal amphotericin B received a BI recommendation due to higher number of reported adverse events in the trials. Amphotericin B deoxycholate should not be used (DII); and fluconazole was rated CI because of a change in epidemiology in some areas in Europe. Removal of central venous catheters is recommended during candidaemia but if catheter retention is a clinical necessity, treatment with an echinocandin is an option (CII(t) ). In chronic disseminated candidiasis therapy, recommendations are liposomal amphotericin B for 8 weeks (AIII), fluconazole for >3 months or other azoles (BIII). Granulocyte transfusions are only an option in desperate cases of patients with Candida disease and neutropenia (CIII).

Invertebrate models of fungal infection

The morbidity, mortality and economic burden associated with fungal infections, together with the emergence of fungal strains resistant to current antimicrobial agents, necessitate broadening our understanding of fungal pathogenesis and discovering new agents to treat these infections. Using invertebrate hosts, especially the nematode Caenorhabditis elegans and the model insects Drosophila melanogaster and Galleria mellonella, could help achieve these goals. The evolutionary conservation of several aspects of the innate immune response between invertebrates and mammals makes the use of these simple hosts an effective and fast screening method for identifying fungal virulence factors and testing potential antifungal compounds. The purpose of this review is to compare several model hosts that have been used in experimental mycology to-date and to describe their different characteristics and contribution to the study of fungal virulence and the detection of compounds with antifungal properties. This article is part of a Special Issue entitled: Animal Models of Disease.

Real-time microscopic observation of Candida biofilm development and effects due to micafungin and fluconazole

To understand the process of Candida biofilm development and the effects of antifungal agents on biofilms, we analyzed real-time data comprising time-lapse images taken at times separated by brief intervals. The growth rate was calculated by measuring the change of biofilm thickness every hour. For the antifungal study, 5-h-old biofilms of Candida albicans were treated with either micafungin (MCFG) or fluconazole (FLCZ). MCFG began to suppress biofilm growth a few minutes after the initiation of the treatment, and this effect was maintained over the course of the observation period. In contrast, the suppressive effects of FLCZ on biofilm growth took longer to manifest: biofilms grew in the first 5 h after treatment, and then their growth was suppressed over the next 10 h, finally producing results similar to those observed with MCFG. MCFG was also involved in the disruption of cells in the biofilms, releasing string-like structures (undefined extracellular component) from the burst hyphae. Thus, MCFG inhibited the detachment of yeast cell clusters from the tips of hyphae. In contrast, FLCZ did not disrupt biofilm cells. MCFG also showed fast antifungal activity against Candida parapsilosis biofilms. In conclusion, our results show that inhibition of glucan synthesis due to MCFG contributed not only to fungicidal activity but also to the immediate suppression of biofilm growth, while FLCZ suppressed growth by inhibiting ergosterol synthesis. Therefore, those characteristic differences should be considered when treating clinical biofilm infections.